CN111801030A

CN111801030A - Lanyard

Info

Publication number: CN111801030A
Application number: CN201880089187.3A
Authority: CN
Inventors: 安德鲁·G·瓦格纳; 特伦特·T·鲍特斯
Original assignee: Milwaukee Electric Tool Corp
Current assignee: Milwaukee Electric Tool Corp
Priority date: 2017-12-21
Filing date: 2018-12-20
Publication date: 2020-10-20
Also published as: US20220295971A1; WO2019126544A1

Abstract

A lanyard is provided having an attachment member, such as a tool retention member, a tie-down latch, or a carabiner. The lanyard includes one or more elastic cords positioned within a sheath. The sheath has a much lower elasticity than the elastic cord. The higher spring constant or modulus of elasticity of the jacket limits the overall extension length of the lanyard in operation. The elastic cord stretches to absorb the energy of the device being dropped until the length of the outer sheath is reached. The attachment member may be attached to the sheath or may comprise a component of the sheath and or the elastic cord. The lanyard allows an elastic response to absorb the energy of a dropped implement and allows the total extended length of the lanyard to be constrained.

Description

Lanyard

Cross Reference to Related Applications

This application claims benefit and priority from U.S. provisional application No.62/609,078, filed on 21/12/2017, the entire contents of which are incorporated herein by reference.

Background

The present invention relates generally to the field of tools. The invention relates in particular to a lanyard for connecting a tool or battery to an anchor point, for example when working aloft. Lanyards are used to attach to/support tools, batteries, components, and/or other devices to provide safety when an operator inadvertently drops the device. The lanyard also protects the tool or equipment from damage caused by a fall.

Disclosure of Invention

One embodiment of the present invention is directed to a lanyard. The lanyard includes a first attachment member, a second attachment member, a sheath, and an elastic cord. The sheath includes a first end coupled to the first attachment member and a second end coupled to the second attachment member. The sheath defines an extended length between the first end and the second end. The elastic cord has a first elastic cord end and a second elastic cord end. Both the first and second elastic cord ends are attached to the first attachment member. The elastic cord defines a loop between the first attachment member and the second attachment member, wherein the elastic cord is stretchable between an unstretched length and a stretched length. The unstretched length is less than the stretched length, wherein the elasticity of the sheath is less than the elasticity of the elastic cord.

Another embodiment of the invention is directed to a lanyard. The lanyard includes a first attachment member, a second attachment member, a sheath, and four or more individual elastic cords. The sheath includes a first end coupled to the first attachment member and a second end coupled to the second attachment member. The sheath defines an extended length between the first end and the second end. The four or more individual elastic cords are disposed within a sheath. Each elastic cord is coupled between first and second attachment members located on opposite ends of the sheath. The elastic cord is stretchable between an unstretched length and a stretched length. The unstretched length is less than the stretched length such that the elasticity of the sheath is less than the elasticity of the elastic cord.

Another embodiment of the invention is directed to a lanyard. The lanyard includes a tool retention member, a carabiner, a sheath, and one or more elastic cords. The sheath includes a first end coupled to the tool retention member and a second end coupled to the carabiner. The second end of the sheath is opposite the first end. The fully extended sheath defines the ultimate tensioned length of the lanyard. The one or more elastic cords are disposed within the sheath and are coupled to the tool retention member on a first end of the sheath and to the carabiner at a second end of the sheath. The one or more elastic cords have a pre-tension length and a tension length. The one or more elastic cords have a tension length less than or equal to a limit tension length of the jacket. The ultimate tensioned length of the jacket is increased by 38% to 115% relative to the pre-tensioned length of the one or more elastic cords.

Alternative exemplary embodiments relate to other features and combinations of features as may be set forth generally in the claims.

Drawings

The present application will become more fully understood from the detailed description given herein below in conjunction with the accompanying drawings, wherein like reference numerals refer to like elements, in which:

FIG. 1 is a perspective view of a lanyard having a carabiner and a loop in accordance with one embodiment.

FIG. 2 is a perspective view of a lanyard having two shackles according to an exemplary embodiment.

FIG. 3 is a cross-sectional view of a lanyard having a carabiner and a loop formed from a single elastic cord beginning at a first end of the sheath and terminating at a second end of the sheath according to an exemplary embodiment.

FIG. 4 is a cross-sectional view of a lanyard having two carabiners and an elastic cord according to an exemplary embodiment.

FIG. 5 is a cross-sectional view of a lanyard having a carabiner and a loop formed from a single elastic cord beginning at and terminating at a first end of the sheath according to an exemplary embodiment.

FIG. 6 is a cross-sectional view of a lanyard including four elastic cords extending from a first end to a second end of the sheath according to an exemplary embodiment.

FIG. 7 is a cross-sectional view of one elastic cord of a lanyard according to an exemplary embodiment.

FIG. 8 is a plan view of a shackle attachment member of a lanyard according to one embodiment.

FIG. 9 is a plan view of an open shackle illustrating a gate separation distance less than a wall separation distance according to an exemplary embodiment.

FIG. 10 is a plan view of a lanyard according to an exemplary embodiment illustrating sections of the lanyard being extended.

Fig. 11 is a plan view of a drop test of the lanyard of fig. 10.

Figure 12 is a data table showing the results of various drop tests performed using the lanyard of figure 10.

Figure 13 is a data table relating to the table of figure 11 showing the results of various drop tests performed using the lanyard of figure 10.

Fig. 14 is a data table relating to the table of fig. 11 showing the results of various drop tests for the lanyard of fig. 10.

Fig. 15 is a data table relating to the table of fig. 11 showing the results of various drop tests for the lanyard of fig. 10.

Fig. 16 is a data table relating to the table of fig. 11 showing the results of various drop tests for the lanyard of fig. 10.

FIG. 17 is a plan view of a lanyard coupled to a tether for a fastening tool in accordance with an exemplary embodiment.

Figure 18 is a data table showing the results of various drop tests performed using the lanyard of figure 13.

FIG. 19 is a data table relating to the table of FIG. 14 showing the results of various drop tests for the lanyard and tether shown in FIG. 13.

Detailed Description

Referring generally to the drawings, various embodiments of a lanyard are illustrated. The lanyard serves as a safety measure for fastening the tool to the anchor point, for example when working aloft. To enhance safety, a lanyard may be coupled to and tie down the tool and tool battery while the tool is operated aloft. Various regulations (e.g., OSHA regulations) may require that a lanyard be present while the operator is using the tool at altitude. When the tool is dropped at high altitudes, the lanyard couples the tool to the anchor point and prevents the tool from dropping. This prevents a safety hazard and also protects the tool from the damaging effects of a fall.

The lanyard is designed to absorb and dissipate the energy of a fall. A lanyard that is too rigid may break or break at the attachment point to the tool or anchor point or along the lanyard itself. Rigid lanyards allow for a predetermined drop length, but typically exhibit brittle material behavior and can accidentally break along the lanyard or at the attachment member. This brittleness-like behavior is due to the rigid lanyard not being able to absorb the energy of a falling object. Elastomeric materials exhibit a much more ductile response to a dropped object, but may not be effective in preventing the object from falling a specified distance. For example, a first object having a first weight will fall a different distance than a second object having a second weight when attached to the same elastic lanyard. Many factors, such as the height of the fall, the weight of the supported object, the spring constant of the elastic material, and other factors, determine the length of deformation required to support the fallen object by the elastic lanyard. For a reliable lanyard, this unpredictability can be problematic.

Applicants have found that the use of a sheath made of a rigid material or a non-elastic material such as nylon surrounding an elastic material such as natural rubber forms a combination lanyard with benefits from both materials. The lanyard has a predictable limit on the amount of total deformation defined by the total extended length of the inelastic sheath. Additionally, the elastic properties of the cords within the lanyard absorb and dissipate a large portion, if not all, of the fall energy. This elastic energy dissipation prevents similar brittle fracture of the jacket at the attachment point or along the lanyard. The non-elastic material reliably limits the drop distance.

One common attachment means at the end of the lanyard is a shackle. The shackle may be quickly attached to an anchor point, tool, or tool tether (coupled to or attached to the tool). The shackle operates the gate in two positions, an open position and a closed position. In the open position, the shackle may receive a loop or a hook. The shackle may be biased toward the closed position such that when the loop is received, the shackle closes around the loop and prevents accidental release. However, typically the loop is larger than the gap or opening created by the shackle between the gate and the first end of the shackle or between the gate and the inner wall of the shackle. This may cause the loop to wind within the loop and may prevent the loop from closing around the loop. The applicant has found that keeping the distance between the gate and the inner wall of the shackle greater than the distance between the gate and the end of the shackle reduces lashing. This is because there is more space for the loop of the lanyard once it passes through the gate (e.g. more space on the shackle) than between the gate and the end of the shackle.

As shown in fig. 1-4, a lanyard 10 is provided. The lanyard 10 includes a sheath 14 having a first end 18 and an opposite second end 22. The first end 18 of the sheath 14 is coupled to a first attachment member 24 and the second end 22 is coupled to a second attachment member 28. The extended sheath 14 defines an extended length between the first end 18 and the second end 22 of the sheath 14. As illustrated in fig. 1-4, the sheath 14 gathers or kinks around the elastic strands 34. Thus, the fully extended sheath 14 is greater than the distance shown. Elastic strands 34 are free to stretch within the length of fully stretched jacket 14. The overall length of the stretched sheath 14 defines a reliable limit to the distance the lanyard 10 will allow the attached device to fall.

The sheath 14 may be made of nylon or other suitable material. For example, the jacket 14 may be made of natural fibers or wool, cashmere, cotton, silk, linen, hemp, and/or other natural fibers. The jacket 14 may be made of synthetic fibers such as rayon, polyester, acrylic, acetate, nylon, polyamide, and/or other polymers. In this application, "nylon" will refer to any member of the polyamide family, such as

nylon

6, 6; nylon 6; nylon 6, 12; nylon 5, 10; and other polyamides. The jacket 14 may be formed from a nylon sheet or composite material such as nylon and rubber. The jacket 14 may be formed from less than 80 strands of nylon per 20 strands of rubber. For example, the jacket 14 may be formed from 74 strands of nylon per 26 strands of rubber. The jacket 14 may be formed of 70 strands of nylon per 30 strands of rubber. The jacket 14 may be formed of 60 strands of nylon per 40 strands of rubber.

In some embodiments, as shown in fig. 1, 3, 5, and 6, the lanyard 10 includes a shackle 26 as the first attachment member 24 and a loop 30 as the second attachment member 28. The loop 30 may be secured to a power tool and the shackle 26 may be secured to a fixed anchor point, such as a building, machine, balcony rail/post, or other mounting structure. In other embodiments, as shown in fig. 2 and 4, the lanyard utilizes the shackle 26 as both the first attachment member 24 and the second attachment member 28. In other embodiments, instead of the shackle 26 or loop 30, the first and

second attachment members

24, 28 may be anything capable of securing the lanyard 10 to a power tool and/or a fixed anchor point. As used herein, a fixed anchor point will refer to any structure to which a lanyard is attached that supports the apparatus during a fall. Examples of fixed anchor points include, but are not limited to, balconies, fences or railings, walls, supports, or other fixed anchor locations for a lanyard.

In some embodiments, as shown in fig. 1 and 2, the lanyard 10 may be coupled to the first and/or

second link members

32, 36. The

attachment members

32 and 36 may have different elastic/inelastic properties than the lanyard 10. The linking

members

32 and 36 may be another lanyard 10 coupled in series. The linking

members

32 and 36 may be coupled in a semi-permanent manner (e.g., by one or more swivels (swiftls) 48) or in a releasable manner (e.g., by one or more shackles 26). For example, the first joining member 32 may join the first end 18 to a first attachment member 24, such as a shackle 26, and the second joining member 36 may join the second end 22 to a second attachment member 28, such as a loop 30 in fig. 1 or another shackle 26 in fig. 2. The first and

second coupling members

32, 36 may also be made of nylon, a nylon composite (e.g., a composite of nylon and rubber), or any other suitable material.

As shown in fig. 1, 2 and 10, the first linking portion 32 includes a loop section 40 and a suture section 44 connecting the loop section 40 to the first end 18 of the sheath 14. As shown in fig. 1, 2, 3, 6, 8, 9, and 10, the shackle 26 may include a swivel 48 that allows the shackle 26 to rotate relative to the sheath 14. In some embodiments, the swivel 48 is fixed and prevents the shackle 26 from rotating. In other embodiments, the swivel 48 resists rotation or allows rotation about the swivel 48 to discrete positions. As shown in fig. 1, 2 and 10, the loop section 40 of the first attachment member 32 loops around the swivel 48 to couple the shackle 26 to the first attachment member 32.

As shown in fig. 3 and 4, the lanyard 10 includes an elastic cord 34 positioned within the sheath 14. The elastic cord 34 includes a set of individual elastic strands 58 made of natural/synthetic rubber or elastomeric material, which set of individual elastic strands 58 are wrapped together to form the elastic cord 34. The elastic cord 34 may be formed of rubber or other suitable elastic material. For example, the elastic strands 34 may be formed from natural rubber, elastomers, elastic polymers, neoprene, unsaturated rubbers (e.g., polyisoprene or nitrile rubber buna-n), saturated rubbers (e.g., ethylene propylene rubber), thermoplastic elastomers (TPE), branched elastin, polysulfide rubber, elastic olefin, and/or other extensible elastic materials. Additionally, the composite jacket 14 or the

attachment portion

32 or 36 may include these materials in proportion to the non-elastic material (e.g., nylon). For example, the jacket 14 or the

attachment portion

32 or 36 may be formed from less than 80 strands of non-elastic material (synthetic or natural, e.g., nylon 6,6) per 20 strands of elastic material (synthetic or natural, e.g., polyisoprene or natural rubber).

In some embodiments, as shown in fig. 3, the elastic cord 34 is coupled to the first attachment member 24 (shackle 26) at the first end 18 and defines the second attachment member 28 (loop 30) outside the second end 22. The jacket 14 surrounds the elastic cord 34 and is coupled to the carabiner 26 at the first end 18. As shown in fig. 4, the elastic cord 34 may be coupled to the carabiner 26 at the first end 18 and to the other carabiner 26 at the second end 22. For example, the loop 30 defined by the elastic cord 34 may be located inside the sheath 14 such that the loop 30 is coupled to the attachment member 28 (e.g., the carabiner 26) or the sheath 14 (e.g., coupled to the sheath 14 at the sheath end 22) and does not form an external loop 30. The sheath 14 may be coupled to the second attachment member 28 (e.g., the shackle 26) by an internal loop 30. The sheath 14 surrounds the elastic cord 34 and is coupled to the carabiner 26 at the first end 18 and the second end 22. In some embodiments, the elastic cord 34 is coupled to the first and second joining members 32, 36 (e.g., as shown in fig. 1 and 2). In the embodiment of fig. 3 and 4, the elastic cord 34 begins at the first end 18 of the sheath 14 and terminates at the second end 22 of the sheath 14.

The

attachment members

24 and 28 may include a shackle 26, a loop 30, a latch, a tether key or tether end, a buckle, a fastener, or another attachment to which a tool or anchor point is attached. The

attachment members

24 and 28 may provide anchor points for the lanyard 10 or may be tool retention members. In operation, a first attachment member 24, such as a shackle 26, may be secured to a fixed anchor point, and a second attachment member 28, such as a loop 30, may be secured to a tool (not shown) used by an operator. In this way, if the operator drops the tool, it is elastically supported by the lanyard 10 until the extended length of the sheath 14 secured to the anchor point is reached. When the tool reaches the extended length of the sheath 14, regardless of weight, drop height, or other characteristics, the inelastic response of the sheath 14 dominates, thereby providing a reliable limit to the distance traveled by a falling object.

In some embodiments, as shown in fig. 5, the elastic cord 34 has a first end 38, a second elastic cord end 42, and a body 46 defined between the first end 38 and the second end 42. Both the first end 38 and the second elastic cord end 42 are coupled to the shackle 26. Body 46 is looped outside of second end 22 of jacket 14 such that body 46 defines loop 30. The elastic strands 34 extend beyond the jacket 14 to form the outer loop 30. As shown in fig. 5, the ring 30 is located on the exterior of the sheath 14. In some embodiments, the loop 30 is located inside the sheath 14 and is coupled to the attachment member 24 or 28 (such as the shackle 26 or the inelastic loop 30 illustrated in fig. 6).

For example, in fig. 5, the loop 30 defined by the elastic cord 34 is located outside of the sheath 14 and defines the second attachment member 28. Thus, in this embodiment, the loop 30 is elastic and there are two

elastic portions

50 and 54 defined by the body 46 of one elastic cord 34.

Resilient portions

50 and 54 of body 46 extend within sheath 14 between first end 18 and second end 22 of sheath 14. For example, both the first and second elastic cord ends 38, 42 are attached to the first attachment member 24, and the elastic cord 34 defines a loop 30 between the first and

second attachment members

24, 28. In other embodiments, the loop 30 defined by the elastic cord 34 is located inside the sheath 14. Loop 30 does not extend beyond jacket 14, but includes

elastic portions

50 and 54 such that both first elastic strand end 38 and second elastic strand end 42 are attached to jacket 14 at first end 18. The inner ring 30 may be connected to the attachment member 28 at the second end 22 of the sheath 14.

The elastic strands 34 may be stretched between an unstretched length and a stretched length. The unstretched length is less than the fully extended length of the sheath 14. Thus, the sheath 14 gathers or kinks around the elastic strands 34. The elasticity of the sheath 14 is less than the elasticity of the elastic cord 34. This configuration enables the elastic cord 34 to stretch to absorb energy as the lanyard 10 supports a falling object. The stretched length of elastic strands 34 may vary between an unstretched length of elastic strands 34 and a fully extended length of jacket 14. Between these limits, the stretched length of the elastic cord 34 elastically absorbs the kinetic energy of the falling object.

In some embodiments, as shown in fig. 6, the lanyard 10 includes four or more individual elastic cords 34 positioned within the sheath 14. In some embodiments, the four or more elastic strands 34 may form the loop 30 such that both the first and second elastic strand ends 38, 42 are attached to the first attachment member 24, and the elastic strands 34 define the loop 30 between the first and

second attachment members

24, 28.

In the embodiment of fig. 6, each elastic cord 34 is independently coupled between attachment member 24 and attachment member 28 at

end

18 or 22 of sheath 14. Each elastic cord 34 is coupled between first attachment member 24 and second attachment member 28 on opposite ends of sheath 14. The elastic strands 34 are capable of being stretched between an unstretched length and a stretched length. The unstretched length is less than the stretched length of sheath 14 and the elasticity of sheath 14 is less than the elasticity of elastic strands 34. As illustrated, the

attachment members

24 and 28 are a hook ring 26 and a non-elastic ring 30 (e.g., nylon and not defined by an elastic cord 34), but the

attachment members

24 and 28 may include any

suitable attachment members

24 or 28. In some embodiments, the jacket 14 may include 5, 6, 7, 8, 9, 10, or more individual elastic strands 34 within the lanyard 10, the elastic strands 34 being individually coupled between the

attachment members

24, 28 or forming the loop 30.

In some embodiments, as shown in fig. 7, the elastic cord 34 includes between 36 and 50 elastic strands 58. Thus, in embodiments such as the one shown in fig. 5, between 72 and 100 elastic strands 58 of rubber are effectively present between the first end 18 and the second end 22 of the jacket 14, but only 36 to 50 elastic strands 58 are present within the elastic cord 34, because there are two

elastic portions

50 and 54 within the jacket 14. Similarly, in embodiments such as the one shown in fig. 6, there are effectively between 144 and 200 elastic strands 58 within the jacket 14 between the first end 18 and the second end 22 because there are 4 individual elastic strands 34 within the jacket 14. The additional elastic strands 34 have between nx 36 and nx 50 elastic strands 58, where N represents the number of elastic strands 34 within the jacket 14. For example, 5 elastic cords 34 (N-5) have between 5 × 36 and 180 and 5 × 50 and 250 elastic strands 58. In some embodiments, two or more elastic strands 34 may form loops 30 within jacket 14 to create four or more

elastic portions

50 and 54. For example, two elastic cords 34 may form the four

elastic portions

50 and 54 and include between 72 and 100 elastic strands 58 made of rubber.

Shackle 26 as shown in fig. 8 and 9 has a body 62, the body 62 having a first end 66 and a second end 70 that functions as a latch or gate 78. The gate 78 is pivotable through a range of motion 82 between a first "closed" position and a second "open" position. For example, when gate 78 is moved from the closed position (illustrated in fig. 1-6) to the open position (illustrated in fig. 7-8), opening 74 is formed between gate 78 and first end 66. The opening 74 is defined when the gate 78 opens between the first end 66 and the second end 70 of the shackle 26.

The shackle 26 may be biased toward the closed position. Applying pressure to gate 78 pivots gate 78 between a closed position, in which gate 78 is engaged with second end 70, and an open position, in which gate 78 has been pivoted the greatest possible distance within range of motion 82, thus maximizing enlarged opening 74. Once the pressure is released, the gate 78 engages the second end 70 in the closed position. The gate 78 may latch and/or lock to the second end 70 of the shackle 26 to securely close the shackle 26 and keep the shackle 26 closed. In some embodiments, gate 78 is biased toward the closed position by a biasing member, such as a spring (not shown). The gate 78 may include a lock or cover (not shown) that rotates or slides to cover the second end 70 and secure the gate 78 in the closed position to prevent accidental opening or release of the shackle 26.

The body 62 of the shackle 26 may optionally be attached to the swivel 48 and includes a first end 66, a first wall portion 86, a second wall portion 90, and a second end 70. The shape of the shackle 26 is defined by the body 62 at a first wall portion 86 and a second wall portion 90. The first wall portion 86 is approximately parallel to the gate 78 when the gate 78 is in the closed position, and the second wall portion 90 is joined to the first wall portion 86. For example, the second wall portion 90 may form an acute, obtuse, or right angle with the first wall portion 86. As illustrated, the second wall portion 90 is at an acute angle to the first wall portion 86, the first wall portion 86 being approximately parallel to the gate 78 in the closed position. Other configurations and embodiments of the shackle 26 are contemplated, including non-parallel angles and/or staggers.

As shown in fig. 8-9, gate separation distance 94 is defined as the distance between gate 78 and second end 70 in the open position in which gate 78 has been pivoted the greatest possible distance within range of motion 82 and opening 74 is maximized. The wall separation distance 98 is defined as the minimum distance between the gate 78 and the first wall portion 86 or the second wall portion 90 within the range of pivotal movement 82. As illustrated in fig. 8, the horizontal wall separation distance 98 is less than the vertical wall separation distance 98. Thus, the wall separation distance 98 is the horizontal wall separation distance 98.

From examining fig. 8-9, we observe two different relationships of gate separation distance 94 to wall separation distance 98 as defined above. In fig. 8, the minimum wall separation distance 98 (e.g., horizontal wall separation distance 98) is less than the gate separation distance 94. In fig. 9, the vertical wall separation distance 98 in the open position is less than the horizontal wall separation distance 98. Thus, the vertical wall separation distance 98 defines the wall separation distance 98. In fig. 9, gate separation distance 94 is less than minimum ("vertical") wall separation distance 98.

The shackle 26 includes a gate 78 pivotally coupled to the first end 66 of the shackle 26. Gate 78 is configured to clasp second end 70 of shackle 26 in the closed position. Rotation of gate 78 to the open position defines a minimum wall separation distance 98 between gate 78 and

walls

86 and 90 of shackle 26 in the open position. The open position also defines a gate separation distance 94 between the second end 70 of the shackle 26 and the gate 78. In some embodiments, a minimum wall separation distance 98 between gate 78 and

walls

86 and 90 is greater than gate separation distance 94 between gate 78 and second end 70 of shackle 26.

In the configuration of fig. 9, first wall portion 86 and second wall portion 90 are arranged relative to gate 78 such that wall separation distance 98 is greater than gate separation distance 94. Thus, in the second position of gate 78, any square or round object, loop or hook large enough to enter shackle 26 through opening 74 may move through gate 78 and allow gate 78 to move back to the closed position. This allows the shackle 26 to securely lock the article or hook. In other words, first wall portion 86 and second wall portion 90 are arranged relative to gate 78 such that the gate 78 is not forced open by an article or hook. Ensuring that the gate separation distance 94 is less than the minimum wall separation distance 98 reduces windup and ensures that the gate 78 can return to the closed position. In this way, the shackle 26 of FIG. 9 provides a simpler use for an operator than the shackle 26 of FIG. 8.

Fig. 10-19 illustrate the lengths of various lanyards 10 measured during testing. Fig. 10 and 17 define two test configurations of the lanyard 10. Fig. 11 illustrates a test method. Fig. 12-16 illustrate measurement results of a test applied to the lanyard 10 of fig. 10. Fig. 18-19 illustrate measurement results of a test applied to the lanyard 10 of fig. 17.

As shown in fig. 10, the overall length 102 of the lanyard 10 can be broken down into six separate sub-lengths: (1) the length 106 of the shackle 26; (2) the length 110 of the ring segment 40; (3) the length 114 of the suture section 44; (4) a length 118 of elastic cord 34 (not shown in FIG. 10) located within sheath 14 between first end 18 and second end 22; (5) the length 122 of the second coupling member 36; (6) length 130 of loop 30. The purpose of the test was to see how the elasticity of these lengths changes when supporting various weights that fall from the height of the unstretched elastic strand 34 above the fixed anchor point (or 2 times the unsupported distance of the unstretched elastic strand 34).

Fig. 11 shows the lanyard 10 in two positions before and after the 2-fold drop test. The drop test height column of the table in fig. 12 uses the designation "2X" if a drop is made with respect to the lanyard 10 as indicated by arrow 170 from a height 174 that is twice the untensioned length 142 of the elastic cord 34 within the lanyard 10. The untensioned length 142 of the lanyard 10 shown in fig. 11 corresponds to the "total length before drop 102" column of the 2 drop test or untensioned length of the lanyard 10. Dashed line 178 indicates the situation where the elastic cord 34 within the lanyard 10 becomes tensioned and stretched. The test is designed not to stretch to the fully extended length of the jacket 14 to test the elastic response of the lanyard 10 system. For the lanyard 10 test of fig. 10, the tool 150 was secured to the loop 30 and dropped from an initial position 182 (2 times the unstretched length of the elastic cord 34) to a final position 186 in which the elastic cord 34 was fully stretched within the sheath 14. The shackle 26 of the lanyard 10 is secured at point 162. As shown in fig. 11, the fully stretched length 190 of the elastic cord 34 and other components of the lanyard 10 corresponds to the "total stretched length 102" column of the table of the 2 drop test height test.

For each weight rating of the lanyard 10, there are three types of drop tests, as explained below. First, the lanyard 10 is subjected to a first 2 drop test while supporting the rated weight of the lanyard 10 and the peak force on the lanyard 10 is measured for this first drop. Second, the lanyard 10 is subjected to an additional 9 independent 2 drop tests while supporting the rated weight of the lanyard 10. The peak force on the lanyard 10 was measured for each of these 9 additional drops. The values listed in the table in fig. 12 represent the maximum independent peak force measured over a total of 10 drops, including a first drop and then 9 drops that support the rated weight of the lanyard 10. Third, the lanyard 10 is subjected to 32 drop tests while supporting twice the rated weight of the lanyard 10, and the peak force is measured for each of the three drops. The maximum independent peak force measured in these three drops is listed in the table of fig. 12. For example, for a 10 pound weight rated lanyard 10 having a total pre-drop length of 921mm, the peak force for the first drop at 10 pounds of support is 82lbf, the maximum peak force for the 10 drops at 10 pounds of support is 123lbf, and the maximum peak force for the 3 drops at 20 pounds of support is 268 lbf.

During the fall, the length 118 of the elastic cord 34 may vary between four separate stages: (1) an initial untensioned stage; (2) a tensioning phase when the length of the elastic cord 34 is less than the length of the untwisted sheath 14; (3) a tensioning phase when the length of the elastic cord 34 is equal to the fully extended length of the sheath 14; and (4) a full stretch stage in which the elastic strands 34 and/or jacket 14 become fully stretched. In the above table, the value of the initial untensioned stage is represented in the column "untensioned length 118 of elastic cord 34" and the value of the fully stretched stage is represented in the column "fully stretched length 118 of elastic cord 34".

When elastic strand 34 becomes as long as untwisted jacket 14, elastic strand 34 is 38% to 115% longer than its untensioned length. When elastic cord 34 becomes as long as untwisted jacket 14, jacket 14 becomes taut and elastic cord 34 and jacket 14 begin to stretch together as a system. As shown in the above table, the relative lengths of the jacket 14 and elastic cord 34 are selected to provide a lower peak force when the weight (e.g., of the tool) is near the rated weight of the lanyard and when the weight on the tool 150 falls from a height greater than the untensioned length 142 of the lanyard 10.

Because the jacket 14 is inelastic, the fully extended length of the jacket 14 generally defines the ultimate tensioned length of the lanyard 10. As the one or more elastic strands 34 within the jacket 14 stretch between the pre-tensioned length and the tensioned length, the one or more elastic strands 34 are unconstrained until the fully extended length of the jacket 14 is reached. When the tensioned length reaches the length of the fully extended sheath 14, the elastic cord 34 reaches the limit tensioned length of the lanyard 10. Thus, the tensioned length of the elastic cord 34 is less than or equal to the ultimate tensioned length of the jacket 14. In some embodiments, the ultimate tensioned length of the jacket 14 is 30% to 125% greater than the pre-tensioned length of the elastic cord 34. In some embodiments, the ultimate tensioned length of the jacket 14 is 38% to 115% greater than the pre-tensioned length of the elastic cord 34. The ultimate tensioned length of the jacket 14 may be between 45% and 110% of the pre-tensioned length of the elastic cord 34. The ultimate tensioned length of the jacket 14 may be between 50% and 105% of the pre-tensioned length of the elastic cord 34. The ultimate tensioned length of the jacket 14 may be between 55% and 100% of the pre-tensioned length of the elastic cord 34.

In the tests described below, the length of the jacket 14 was selected to study the elastic properties of the elastic cord 34. As such, the length of the jacket 14 is selected to be greater than the elastic response of the lanyard 10 system to prevent the extreme tensioned length of the jacket 14 from interfering with the test results.

As shown in the table in fig. 12, the test data for the lanyard 10 of different weight ratings indicates a corresponding stretched length of the 6 sub-lengths described above when the lanyard 10 is subjected to different drop tests. In all drop tests listed in the table of fig. 12, the length 106 of the shackle 26 was held constant at 86mm and did not change as the lanyard 10 was stretched. Similarly, in all tests, the length 114 of the stitched section 44 of the sheath 14 was held constant at 36mm and the length 122 of the second joining member 36 (e.g., nylon) was held constant at 36 mm. In other words, none of the

lengths

106, 114, 122 changes as the lanyard 10 is stretched when dropped. Because the jacket 14 has a greater modulus of elasticity (spring constant) and lower elasticity than the elastic cord 34, the jacket 14 limits the length that the lanyard 10 can be stretched.

As related to the results shown in fig. 12, fig. 13-16 illustrate data from drop tests respectively related to: a 10lb. weight rated lanyard 10 having a pre-drop total length 102 of 921 mm; a 10lb. weight rated lanyard 10 having a pre-drop total length 102 of 1381 mm; 15lb. weight rated lanyard 10; and 50lb. weight rated lanyard 10.

In another embodiment of the lanyard 192 shown in fig. 17, the lanyard 192 includes, in series: the first shackle 194; a swivel member 196; a first linkage 198, the first linkage 198 comprising a loop section 202 and a stitched section 206; a sheath 210; a second joining member 214, the second joining member 214 comprising a suture section 218 and a loop section 222; a second shackle 226; a tether 230; and a tether attachment member 236. As in the previous embodiment, the elastic cord 34 (not shown in fig. 17) is disposed within the sheath 210 and coupled between the stitched section 206 of the first joining member 198 and the stitched section 218 of the second joining member 214.

As shown in fig. 17, the overall length 240 of the lanyard 192 can be broken down into 9 separate sub-lengths: (1) length 244 of first shackle 194; (2) a length 248 of the ring segment 202; (3) length 252 of suture section 206; (4) an unstretched length 256 of elastic strand 34 (not shown in fig. 17) located between stitched section 206 of first attachment member 198 and stitched section 218 of second attachment member 214 and within sheath 210; (5) the length 260 of the suture section 218; (6) the length 264 of the ring segment 222; (7) length 268 of second shackle 226; (8) the length 272 of the tether 230; and (9) the length 276 of the tether attachment member 236. Additionally, the overall length 240 may be subdivided into a first sub-length 280 from the first shackle 194 to the second shackle 226 and a tether 230 sub-length 284 from the tether 230 to the tether attachment member 236.

The same drop test illustrated in fig. 11 was performed by lanyard 192 in the same manner as described above, and the results are listed in the table shown in fig. 18. In all drop tests listed in the table of fig. 18, both length 244 of first shackle 194 and length 268 of second shackle 226 were held constant at 86mm and 96mm, respectively, and did not change as lanyard 192 was stretched. Similarly, in all tests, both the length 252 of the suture section 206 of the sheath 14 and the length 260 of the suture section 218 of the sheath 14 were held constant at 36 mm. In other words, none of the

lengths

244, 252, 260, and 268 will change as the lanyard 192 is stretched when dropped. This illustrates the sheath 14 having a greater modulus or spring constant and lower elasticity than the elastic cord 34. Thus, the length of the jacket 14 defines a practical limit to the total extension of the lanyard 10. The elastic cord 34 is free to stretch and absorb the energy of the fall until the extended length of the sheath 14 is reached.

As related to the results shown in fig. 18, fig. 19 illustrates data of drop tests respectively related to lanyard 192. In particular, fig. 19 shows the elongation of the elastic cord 34 for a 2-fold test with respect to: (1) a first drop at rated weight; (2) maximum elongation after 10 drops at rated weight; and (3) maximum elongation after 3 drops at twice the rated weight of the lanyard 192.

For the purposes of this disclosure, the term "coupled" means that two components are joined to each other, either directly or indirectly. This combination may be stationary in nature or movable in nature. Such joining may be achieved with the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members being attached to one another or with the two members and any additional members being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature.

It should be understood that the drawings illustrate exemplary embodiments in detail, and that the application is not limited to the details or methodology set forth in the description or illustrated in the drawings. It is also to be understood that the terminology is for the purpose of description and should not be regarded as limiting.

Other modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only. The construction and arrangement shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of positions or discrete elements may be altered or varied. The order or sequence of any process, logical algorithm, or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present inventions.

Claims

1. A lanyard, comprising:

a first attachment member;

a second attachment member;

a sheath including a first end coupled to the first attachment member and a second end coupled to the second attachment member, the sheath defining an extended length between the first end and the second end; and

an elastic cord having a first elastic cord end and a second elastic cord end, wherein both the first and second elastic cord ends are attached to the first attachment member, the elastic cord defining a loop between the first and second attachment members, wherein the elastic cord is stretchable between an unstretched length and a stretched length, and the unstretched length is less than the stretched length, wherein the sheath has an elasticity that is less than the elasticity of the elastic cord.

2. The lanyard of claim 1 wherein the sheath is formed from a nylon sheet.

3. The lanyard of claim 1 wherein the elastic cord is natural rubber.

4. The lanyard of claim 1 wherein the loop defined by the elastic cord is located outside of the sheath, the loop defining the second attachment member.

5. The lanyard of claim 1 wherein the loop defined by the elastic cord is located inside of the sheath, the sheath being coupled to the second attachment member.

6. The lanyard of claim 1 wherein the elastic cord comprises between 36 and 50 individual elastic strands.

7. The lanyard of claim 1 wherein at least one attachment member is a shackle.

8. The lanyard of claim 7 wherein the carabiner includes a gate pivotably coupled to a first end of the carabiner and configured to clasp a second end of the carabiner in a closed position, wherein rotation of the gate to an open position defines a minimum wall separation distance between the gate and one or more walls of the carabiner in the open position and a gate separation distance between the second end of the carabiner and the gate, wherein the minimum wall separation distance is greater than the gate separation distance.

9. A lanyard, comprising:

a first attachment member;

a second attachment member;

four or more individual elastic strands within the sheath, each elastic strand coupled between the first and second attachment members on opposite ends of the sheath, wherein the elastic strands are stretchable between an unstretched length and a stretched length, and the unstretched length is less than the stretched length, wherein the sheath has an elasticity less than an elasticity of the elastic strands.

10. The lanyard of claim 9 wherein the sheath is a composite of nylon and natural rubber.

11. The lanyard of claim 10 wherein the sheath is made from 74% nylon and 26% natural rubber.

12. The lanyard of claim 9 further comprising a loop attachment member coupled to the first end or the second end of the sheath.

13. The lanyard of claim 9 wherein the four or more individual elastic cords comprise between 144 and 200 individual elastic strands.

14. The lanyard of claim 9 further comprising a carabiner as the first attachment member or the second attachment member, wherein the carabiner comprises a gate pivotably coupled to a first end of the carabiner and configured to clasp a second end of the carabiner in a closed position, wherein rotation of the gate to an open position defines a minimum wall separation distance between the gate and one or more walls of the carabiner in the open position and a gate separation distance between the second end of the carabiner and the gate, wherein the minimum wall separation distance is greater than the gate separation distance.

15. A lanyard, comprising:

a tool holding member;

a shackle;

a sheath including a first end coupled to the tool retention member and a second end coupled to the carabiner, the second end opposite the first end, the fully extended sheath defining an ultimate tensioning length; and

one or more elastic cords located within the sheath and coupled to the tool retention member on a first end of the sheath and to the carabiner at a second end of the sheath, the one or more elastic cords having a pre-tension length and a tension length, wherein the tension length of the one or more elastic cords is less than or equal to the ultimate tension length of the sheath, and wherein the ultimate tension length of the sheath is increased by 38% to 115% relative to the pre-tension length of the one or more elastic cords.

16. The lanyard of claim 15 wherein the tool retention member is a loop.

17. The lanyard of claim 15 wherein the tool retention member is a tie-down buckle.

18. The lanyard of claim 15 wherein the tool retention member is a carabiner.

19. The lanyard of claim 15 comprising two elastic cords in the form of loops comprising between 72 and 100 elastic strands of rubber.

20. The lanyard of claim 15 further comprising a shackle attachment member, wherein the shackle comprises a gate pivotably coupled to a first end of the shackle and configured to clasp a second end of the shackle in a closed position, wherein rotation of the gate to an open position defines a minimum wall separation distance between the gate and one or more walls of the shackle in the open position and a gate separation distance between the second end of the shackle and the gate, wherein the minimum wall separation distance is greater than the gate separation distance.